Microstructures such as microelectromechanical devices (hereafter MEMS device) having deformable elements may suffer from device failure when the deformable elements deform plastically. For example, the operation states (e.g. the “natural resting state) of the MEMS device change due to plastic deformation which in turn cause differences between the states to vary over time. The change of the states and variation of the relative distances may affect the performance of the MEMS devices, especially those devices (e.g. micromirrors) whose operations depend upon the differences between the states (e.g. the ON and OFF state of the micromirrors). When the plastic deformation exceeds a certain amount, the states or the difference between the states exceeds the tolerable amount—causing device failure.
Therefore, a method is desired for processing the deformable element of a MEMS device so as to improve the performance and lifetime of the device.